function a=coefLagr(x,y)
	
	% calcul coeficienti polinom Lagrange
	x = x( : );
	n = length( x );	%polinomul are gradul n-1;
	v = ones( n, n );
	for i = 2 : n
		v( :, i ) = v( :, i - 1 ) .* x;
	endfor
	a = v \ y;

endfunction
